The invention relates to a gamma correction circuit comprising a non-linear differential amplifier having an input coupled to a circuit input for the supply of a signal to be gamma-corrected and comprising two emitter-coupled transistors and a current source present in the transistor-emitter lead, and a current-mirror circuit coupled to a differential amplifier output and an output of the gamma correction circuit for the supply of a gamma-corrected signal.
a circuit of this type is described in European Patent Application No. 0,116,398. The non-linear differential amplifier is, to this end, formed with several numbers of series-connected diodes. With the aid of the current mirror circuit, the currents are maintained equal to each other so that the gamma-corrected signal has a gamma characteristic at the circuit output which is independent of temperature variations in the circuit components. The patent application describes three embodiments with many circuit components in a complicated circuit structure in each of them and particularly with a striking number of diodes.